The invention relates to a radio receiver according to U.S. Pat. No. 4,862,513, BRAGAS.
German Patent Disclosure DE-OS 35 36 820, BRAGAS & BUSCH, published Apr. 16, 1987, discloses a traffic radio decoder that is equipped to process digital signals. The digital signals are obtained by demodulation of an auxiliary carrier that is broadcast via radio stations along with an FM radio program. Even with RM radio stations, the digital signals can be transmitted by phase modulation of the carrier and recovered in a phase detector. With this kind of transmission, standardized texts, worded in accordance with the formatting principles, like the traffic announcements broadcast in the clear, can be called up from memory locations. The standard texts are present in memories of the receiver and are called up by the digital signals by suitably addressing the memory locations or memory fields. This avoids an annoying interruption of the ongoing radio program. Furthermore, traffic announcements can be transmitted continuously, so that the driver is always up to date.
Transmitting digital signals as addresses of memory locations makes it possible to use a relatively low bit rate for an individual traffic advisory. As a result, a great number of traffic advisories can be repeated cyclically, and they can also be transmitted uniformly mixed, regionally and super-regionally, via the transmitter networks.
Traffic announcements that include not only place information and factual information but also recommended detours require a particularly large informational scope. Such recommended detours are given whenever a traffic obstruction prevails for a relatively long time with a large amount of oncoming traffic, and the driver would reach his destination faster over the longer distance of the detour, sometimes leading through towns and cities, rather than if he were to wait until the traffic obstruction was eliminated.